The importance of mineral nutrition on dental caries occurrence in man has so far been limited to fluoride where a caries reduction of 50-60% in children has been demonstrated. The nutrition of other minerals has periodically been suggested as a factor in caries development but the association is primarily based upon epidemiological observations. Many experimental studies describing the interactions between metals and caries mostly in rats have been reported, but the results are difficult to interpret for several reasons. Many studies did not take into account the importance of early developmental effects of nutrition. This is important because nutritional demands are high during fetal growth including that for tooth development. Secondly, many of the studies involved metals such as boron which are of unknown nutritional importance. Lastly, most of the studies utilized dietary levels of metals that had no relationship to the nutrition of the experimental animal. The purpose of the proposed research is to investigate the influence of mineral status other than fluoride on tooth development and occurrence of caries using the albino rat as the animal model. Each study would utilize physiological levels of metals known to be relevant to health including the essential trace metals zinc, iron, copper, selenium, manganese, the macroelement magnesium, and the non-essential trace metals lead and cadmium. The vehicle for these mineral factors each to be fed at four levels is a semi-purified, high sucrose, caries-promoting diet. Rats would receive the different treatment levels throughout gestation and lactation representing developmental or pre-eruptive effects. Each study would continue for an additional six weeks with rat pups receiving the identical treatment level as the dam, representing post-eruptive effects. Uniform production of caries would be produced by oral innoculation of rat pups at day 19 of lactation with a 24 hour culture of Streptococcus mutans. Methods of assessment include physical characteristics of rat molars, chemical composition of teeth and supporting bone and quantitation of molar caries compared to non-innoculated controls. Data would be useful at least on a conceptual basis for clarifying the potential of minerals other than fluoride to modify dental caries.